1. Field of the Invention
The present invention provides methods of uniformly introducing treating fluids into subterranean producing zones having perforation tunnels formed therein.
2. Description of the Prior Art
After a well bore is drilled and completed in a subterranean producing zone including the formation of perforation tunnels through casing and cement into the zone, it is often necessary to introduce a treating fluid into the zone. For example, the producing zone can be stimulated by introducing an aqueous acid solution into the producing zone to thereby increase its porosity and the production of hydrocarbons therefrom. In order to insure that the producing zone is contacted by the treating fluid uniformly, it has heretofore been the practice to pack the perforation tunnels in the subterranean zone with a particulate solid diverting agent. The presence of the diverting agent in the perforation tunnels causes the treating fluid introduced therein to be uniformly distributed between all of the perforations whereby the subterranean zone is uniformly treated.
A problem in the use of the above described procedure is that the particulate solid diverting agent must subsequently be removed from the perforation tunnels. This has been accomplished by contacting the particulate solid diverting agent with a fluid which dissolves the diverting agent, i.e., water, oil, xylene, etc. While the clean-up procedure required can be successful in removing the diverting agent, it often entails considerable time and expense to carry out.
Thus, there are needs for improved methods of uniformly introducing a treating fluid into a subterranean producing zone by way of perforation tunnels therein without the requirement of removing the particulate solid diverting agent by contacting it with a clean-up solution.